package com.lx.gulimall.search.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
import com.lx.common.to.es.SkuEsModel;
import com.lx.common.utils.R;
import com.lx.gulimall.search.config.GulimallElasticSearchConfig;
import com.lx.gulimall.search.constant.EsConstant;
import com.lx.gulimall.search.feign.ProductFeignService;
import com.lx.gulimall.search.service.MallSearchService;
import com.lx.gulimall.search.vo.AttrResponseVo;
import com.lx.gulimall.search.vo.BrandVo;
import com.lx.gulimall.search.vo.SearchParam;
import com.lx.gulimall.search.vo.SearchResult;
import org.apache.lucene.search.join.ScoreMode;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.NestedQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.RangeQueryBuilder;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.bucket.nested.NestedAggregationBuilder;
import org.elasticsearch.search.aggregations.bucket.nested.ParsedNested;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedLongTerms;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedStringTerms;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregationBuilder;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortOrder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.StringUtils;

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

/**
 * @author lixun Email:lx3027@126.com
 * @create 2021-07-25 17:13
 */
@Service
public class MallSearchServiceImpl implements MallSearchService {

    @Autowired
    private RestHighLevelClient client;

    @Autowired
    private ProductFeignService productFeignService;

    @Override
    public SearchResult search(SearchParam param) {
        // 1.动态构建出查询所需要的dsl语句
        SearchResult result = null;
        // 2.准备索引请求
        SearchRequest searchRequest = buildSearchRequest(param);
        try {
            // 3.执行检索请求
            SearchResponse search = client.search(searchRequest, GulimallElasticSearchConfig.COMMON_OPTIONS);
            // 4.分析 响应数据封装成我们需要的格式
            result = buildSearchResult(search, param);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return result;
    }

    /**
     * 执行结果数据
     *
     * @return
     */
    private SearchResult buildSearchResult(SearchResponse search, SearchParam param) {

        SearchResult result = new SearchResult();
        // 1.返回的所有查询到的商品
        List<SkuEsModel> skuEs = new ArrayList<>();
        SearchHits hits = search.getHits();
        if (hits.getHits().length > 0 && hits.getHits() != null) {
            for (SearchHit hit : hits.getHits()) {
                // 这里接收的是json字符串
                String sourceAsString = hit.getSourceAsString();
                // 这里把json转换成我们想要的数据
                SkuEsModel skuEsModel = JSON.parseObject(sourceAsString, SkuEsModel.class);
                if (!StringUtils.isEmpty(param.getKeyword())) {
                    HighlightField skuTitle = hit.getHighlightFields().get("skuTitle");
                    String string = skuTitle.getFragments()[0].string();
                    skuEsModel.setSkuTitle(string);
                }
                skuEs.add(skuEsModel);
            }
        }
        result.setProducts(skuEs);

        // 2.当前商品设计到的所有属性信息
        List<SearchResult.AttrVo> attrVos = new ArrayList<>();
        ParsedNested attr_agg = search.getAggregations().get("attr_agg");
        ParsedLongTerms attr_id_agg = attr_agg.getAggregations().get("attr_id_agg");
        for (Terms.Bucket bucket : attr_id_agg.getBuckets()) {
            SearchResult.AttrVo attrVo = new SearchResult.AttrVo();
            long attrId = bucket.getKeyAsNumber().longValue();
            String attrName = ((ParsedStringTerms) bucket.getAggregations().get("attr_name_agg")).getBuckets().get(0).getKeyAsString();
            List<String> attrValues = ((ParsedStringTerms) bucket.getAggregations().get("attr_value_agg")).getBuckets().stream().map(item -> {
                String keyAsString = ((Terms.Bucket) item).getKeyAsString();
                return keyAsString;
            }).collect(Collectors.toList());
            attrVo.setAttrId(attrId);
            attrVo.setAttrName(attrName);
            attrVo.setAttrValue(attrValues);

            attrVos.add(attrVo);
        }
        result.setAttrs(attrVos);
        // 3.当前商品涉及到的所有品牌信息
        List<SearchResult.BrandVo> brandVos = new ArrayList<>();
        ParsedLongTerms brand_agg = search.getAggregations().get("brand_agg");
        for (Terms.Bucket bucket : brand_agg.getBuckets()) {
            SearchResult.BrandVo brandVo = new SearchResult.BrandVo();
            // 1.品牌的Id
            long brandId = bucket.getKeyAsNumber().longValue();
            // 2.品牌的name
            String brandName = ((ParsedStringTerms) bucket.getAggregations().get("brand_name_agg")).getBuckets().get(0).getKeyAsString();
            // 3.品牌的img
            String brandImg = ((ParsedStringTerms) bucket.getAggregations().get("brand_img_agg")).getBuckets().get(0).getKeyAsString();
            brandVo.setBrandId(brandId);
            brandVo.setBrandName(brandName);
            brandVo.setBrandImg(brandImg);
            brandVos.add(brandVo);
        }
        result.setBrands(brandVos);


        // 4.当前商品涉及到的所有分类信息
        ParsedLongTerms catalog_agg = search.getAggregations().get("catalog_agg");
        List<SearchResult.CatalogVo> catalogVos = new ArrayList<>();
        for (Terms.Bucket bucket : catalog_agg.getBuckets()) {
            SearchResult.CatalogVo catalogVo = new SearchResult.CatalogVo();
            // 得到分类Id
            String keyAsString = bucket.getKeyAsString();
            catalogVo.setCatalogId(Long.parseLong(keyAsString));
            // 的到分类名
            ParsedStringTerms catalog_name_agg = bucket.getAggregations().get("catalog_name_agg");
            String catalog_name = catalog_name_agg.getBuckets().get(0).getKeyAsString();
            catalogVo.setCatalogName(catalog_name);
            catalogVos.add(catalogVo);
        }
        result.setCatalogs(catalogVos);


        // 5.分页信息 -> 页码
        result.setPageNum(param.getPageNum());
        // 6.分页信息 ->总记录数
        long totalHits = hits.getTotalHits().value;
        result.setTotal(totalHits);
        // 7.分页信息 -> 总页码 -> 计算  (11+2-1)/2
        int totalPages = (int) ((totalHits + EsConstant.PRODUCT_PAGESIZE - 1) / EsConstant.PRODUCT_PAGESIZE);
        result.setTotalPages(totalPages);
        List<Integer> pageNavs = new ArrayList<>();
        for (int i = 1; i <= totalPages; i++) {
            pageNavs.add(i);
        }
        result.setPageNavs(pageNavs);


        // 6.构建面包屑导航功能
        if (param.getAttrs() != null && param.getAttrs().size() > 0) {
            List<SearchResult.NavVo> navVos = param.getAttrs().stream().map(attr -> {
                SearchResult.NavVo navVo = new SearchResult.NavVo();
                String[] s = attr.split("_");
                navVo.setNavValue(s[1]);
                R r = productFeignService.attrInfo(Long.parseLong(s[0]));
                // 将已选择的请求参数添加进去 前端页面进行排除
                result.getAttrIds().add(Long.parseLong(s[0]));
                if (r.getCode() == 0) {
                    AttrResponseVo data = r.getData("attr", new TypeReference<AttrResponseVo>() {
                    });
                    navVo.setNavName(data.getAttrName());
                } else {
                    // 失败了就拿id作为名字
                    navVo.setNavName(s[0]);
                }
                // 拿到所有查询条件 替换查询条件
                String replace = replaceQueryString(param, attr, "attrs");
                navVo.setLink("http://search.gulimall.com/list.html?" + replace);
                return navVo;
            }).collect(Collectors.toList());
            result.setNavs(navVos);
        }

        // 品牌
        if (param.getBrandId() != null && param.getBrandId().size() > 0) {
            List<SearchResult.NavVo> navs = result.getNavs();
            SearchResult.NavVo navVo = new SearchResult.NavVo();
            navVo.setNavName("品牌");
            // TODO 远程查询所有品牌
            R r = productFeignService.brandInfo(param.getBrandId());
            if (r.getCode() == 0) {
                List<BrandVo> brand = r.getData("brand", new TypeReference<List<BrandVo>>() {
                });
                StringBuffer buffer = new StringBuffer();
                // 替换所有品牌ID
                String replace = "";
                for (BrandVo brandVo : brand) {
                    buffer.append(brandVo.getBrandName() + ";");
                    replace = replaceQueryString(param, brandVo.getBrandId() + "", "brandId");
                }
                navVo.setNavValue(buffer.toString());
                navVo.setLink("http://search.gulimall.com/list.html?" + replace);
            }
            navs.add(navVo);
        }
        return result;
    }

    /**
     * 替换字符
     * key ：需要替换的key
     */
    private String replaceQueryString(SearchParam Param, String value, String key) {
        String encode = null;
        try {
            encode = URLEncoder.encode(value, "UTF-8");
            // 浏览器对空格的编码和java的不一样
            encode = encode.replace("+", "%20");
            encode = encode.replace("%28", "(").replace("%29", ")");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return Param.get_queryString().replace("&" + key + "=" + encode, "");
    }

    /**
     * 准备检索请求
     * 模糊匹配，过滤（按照属性，分类，品牌，价格区间，库存）,排序，分页，高亮,聚合分析
     * 重点在 ElasticSearch 语法上 ----> dsl.json文件中
     *
     * @return
     */
    private SearchRequest buildSearchRequest(SearchParam param) {

        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();

        /**
         * 模糊匹配，过滤（按照属性，分类，品牌，价格区间，库存）
         */
        BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
        // 关键词
        if (!StringUtils.isEmpty(param.getKeyword())) {
            boolQuery.must(QueryBuilders.matchQuery("skuTitle", param.getKeyword()));
        }

        // 分类
        if (param.getCatalog3Id() != null) {
            boolQuery.filter(QueryBuilders.termQuery("catalogId", param.getCatalog3Id()));
        }

        // 品牌
        if (param.getBrandId() != null && param.getBrandId().size() > 0) {
            boolQuery.filter(QueryBuilders.termsQuery("terms", param.getBrandId()));
        }

        // 属性
        if (param.getAttrs() != null && param.getAttrs().size() > 0) {
            for (String attrStr : param.getAttrs()) {
                BoolQueryBuilder queryBuilder = QueryBuilders.boolQuery();
                String[] s = attrStr.split("_");
                String attrId = s[0];
                String[] attrValue = s[1].split(":");
                queryBuilder.must(QueryBuilders.termQuery("attrs.attrId", attrId));
                queryBuilder.must(QueryBuilders.termsQuery("attrs.attrValue", attrValue));
                NestedQueryBuilder nestedQuery = QueryBuilders.nestedQuery("attrs", queryBuilder, ScoreMode.None);
                boolQuery.filter(nestedQuery);
            }

        }

        // 库存
        if (param.getHasStock() != null) {
            boolQuery.filter(QueryBuilders.termsQuery("hasStock", param.getHasStock() == 1));
        }

        // 价格区间
        if (!StringUtils.isEmpty(param.getSkuPrice())) {
            RangeQueryBuilder rangeQuery = QueryBuilders.rangeQuery("skuPrice");
            String[] s = param.getSkuPrice().split("_");
            if (s.length == 2) {
                // 区间
                rangeQuery.gte(s[0]).lte(s[1]);
            } else if (s.length == 1) {
                if (param.getSkuPrice().startsWith("_")) {
                    rangeQuery.lte(s[0]);
                }
                if (param.getSkuPrice().endsWith("_")) {
                    rangeQuery.gte(s[0]);
                }
            }
            boolQuery.filter(rangeQuery);
        }

        sourceBuilder.query(boolQuery);

        /**
         * 排序，分页，高亮
         */

        // 排序
        if (!StringUtils.isEmpty(param.getSort())) {
            String sort = param.getSort();
            String[] s = sort.split("_");
            SortOrder order = s[1].equalsIgnoreCase("asc") ? SortOrder.ASC : SortOrder.DESC;
            sourceBuilder.sort(s[0], order);
        }
        // 分页
        sourceBuilder.from((param.getPageNum() - 1) * EsConstant.PRODUCT_PAGESIZE);
        sourceBuilder.size(EsConstant.PRODUCT_PAGESIZE);

        // 高亮
        if (!StringUtils.isEmpty(param.getKeyword())) {
            HighlightBuilder builder = new HighlightBuilder();
            builder.field("skuTitle");
            builder.preTags("<b style='color:red'>");
            builder.postTags("</b>");
            sourceBuilder.highlighter(builder);
        }

        /**
         * 聚合分析
         */

        // 聚合品牌 brand
        TermsAggregationBuilder brand_agg = AggregationBuilders.terms("brand_agg");
        brand_agg.field("brandId").size(50);
        brand_agg.subAggregation(AggregationBuilders.terms("brand_name_agg").field("brandName").size(1));
        brand_agg.subAggregation(AggregationBuilders.terms("brand_img_agg").field("brandImg").size(1));
        sourceBuilder.aggregation(brand_agg);

        // 聚合三级分类 Catalog
        TermsAggregationBuilder catalog_agg = AggregationBuilders.terms("catalog_agg");
        catalog_agg.field("catalogId").size(20);
        catalog_agg.subAggregation(AggregationBuilders.terms("catalog_name_agg").field("catalogName").size(1));
        sourceBuilder.aggregation(catalog_agg);

        // 聚合属性 attr
        NestedAggregationBuilder attr_agg = AggregationBuilders.nested("attr_agg", "attrs");
        TermsAggregationBuilder attr_id_agg = AggregationBuilders.terms("attr_id_agg").field("attrs.attrId");
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_name_agg").field("attrs.attrName").size(1));
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_value_agg").field("attrs.attrValue").size(50));
        attr_agg.subAggregation(attr_id_agg);
        sourceBuilder.aggregation(attr_agg);


        String s = sourceBuilder.toString();
        System.out.println("构建的DSL" + s);

        SearchRequest searchRequest = new SearchRequest(new String[]{EsConstant.PRODUCT_INDEX}, sourceBuilder);

        return searchRequest;
    }

}
